通分(1)6c/a²b与c/3ab² (2)x - y/2x+3y与xy/(x+y)²(3)2mn/4m²— 9与4m²n+6m/8m²—27急
问题描述:
通分(1)6c/a²b与c/3ab² (2)x - y/2x+3y与xy/(x+y)²
(3)2mn/4m²— 9与4m²n+6m/8m²—27
急
答
(1)6c/a²b=18bc/a²b² c/3ab² =ac/3a²b² (2)x - y/2x+3y=(x-y)(x+y)²/(2x+3y)(x+y)² xy/(x+y)²=xy(2x+3y)/(2x+3y)(x+y)² (3)2mn/4m²— 9=2mn(8...